People _____with more than just words.
Snowflakes____single ice crystals or multi-crystal aggregates.
| Structure | Description | Examples |
| Verb | Words used to indicate existence, action or belonging | The escallonia plant is especially popular because of the many varieties available The forests of British Colombia produce about half of Canada’s marketable wood. |
| Verb phrase | A group of words containing a verb and related words | Thunderstorms frequently occur in the afternoon. Although they are not often seen, coyotes have been living among humans for centuries. |
| Auxiliary verb | Special verbs that assist the main verb in a verb phrase | The gypsy moth, which is spreading across North America, has eaten the leaves of 13 million acres of trees Some species of trees do not bear fruit for several years. |
| Modal verb | Auxiliary verbs expressing mood | The ocean can store great amounts of heat. Every home should have an emergency kit an accessible location. |
| Base form | Present form | Past form | Present participle | Past participle |
| call | call/calls | called | calling | called |
| cry | cry/cries | cried | crying | cried |
| be | am/is/are | was/were | being | been |
| build | build/builds | built | building | built |
| do | do/does | did | doing | done |
| fly | fly/flies | flew | flying | flown |
| have | have/has | had | having | had |
| speak | speak/speaks | spoke | speaking | spoken |
Auxiliary verbs are special verbs that accompany and assist the main verb. Auxiliary verbs help the main verb express its meaning:
The most common auxiliary verbs are be, have, and do.
| The two largest national chains are opening new restaurants in the suburbs. By the age of twenty, Elvis Presley had recorded several songs. When I was in high school, I did not like getting up early. |
Adverbs modify verbs and are usually placed after the first auxiliary verb. In the following sentences, adverbs are in italics.
| This factory has never had any serious accidents among the workers. I had not been speeding, so I don’t know why I got a traffic ticket. The restaurant has recently been inspected for adherence to the health code. |
The tenses of a verb indicate when an action occurs, a relationship, or the state of things. Verbs have several different tenses that indicate present, past, and future time.
Simple tenses are present tense, past tense and will+the indfinitive.
Progressive tenses express continuous actions and behaviors. Their form is the auxiliary verb be + the present participle of the verb.
The perfect tense is have/has/had/will have+the past participle of the verb
The perfect progressive tense is in the form of have been/has been/had been/will have been+the present participle of the word.
Note: Past participle and present participles cannot be used alone as verbs; to act as verbs, they must be assisted by auxiliary verbs.
| Tense | Examples |
| simple present | Thunderstorm form when an air parcel becomes buoyant and rises. |
| present continuous tense | Astronomers are now looking for planets beyond our solar system. |
| present perfect tense | Sophisticated detection devices have brought the extent of pollution to the public’s attention. |
| present perfect continuous tense | For more than thirty years, Anna Deavere Smith has been writing and performing one-woman plays. |
| simple past tense | Each time the moneychangers of ancient Greece made an exchange, they charged a fee. |
| past continuous tense | Between 1945 and 1980, the federal government was spending 75 percent of its transportation budget on highways. |
| past perfect tense | Before the two Germanys reunited, East Germany had built the Berlin Wall to keep East Berliners from crossing into the West. |
| past perfect continuous tense | Humans had been dreaming of flight for centuries before the Wright brothers built their glider. |
| simple future tense | Global warming will cause flooding, windstorms, and killer heat waves. |
| future continuous tense | The number of teenagers will be steadily increasing for the next decade. |
| future perfect tense | Millions of children will have experienced famine or war by the time they reach their teens. |
| future perfect continuous tense | When I enter graduate school, I will have been studying foreign language for twelve years. |
Some words or phrases can be used as time markers to indicate when an action or behavior occurs, whether in the present, past, or future.
| Present | Past | Future |
| today at present now usually every time in the current period currently | yesterday in the past ago formerly in the 1980’s in the former period during the sixth century | tomorrow in the future from now next week by 2050 in the coming period during the next decade |
TIPS: When writing sentences, use the correct tense to express the meaning. In the sentence, the tense should be consistent with the time marker, and the tense should be coordinated.
| Incorrect | Correct |
| In the sixteenth century, Leonardo da Vinci studies many topics and makes important discoveries. | In the sixteenth century, Leonardo da Vinci studied many topics and made important discoveries. |
| I believe that art teaches us how to live, so art was a necessary part of a good education. | I believe that art teaches us how to live, so art is a necessary part of a good education. |
Modal verbs are auxiliary verbs that modify the main verb. Modal verbs express mood or attitude, indicating that the action of the main verb is certain, possible, probable, desirable, necessary, or common. Modal verbs can also be used to express intention, make suggestions, or state preferences.
Modal verbs can express present, future and past tenses, and can also express ongoing actions.
| Modal | What it shows | Examples |
| will | certainty in the present or future intention | A baby will cry when it is hungry or frightened. |
| be going to | future possibilities intention | It looks like it‘s going to rain The committee is going to study emerging technologies. |
| shall | intention | We shall work hard to accomplish our goals. |
| can | present possibility
ability now available | The vampire bat can infect farm animals with the deadly rabies virus. Many children can ride a bicycle by the age of six |
| could | past possibility
past ability
desirability | I couldn’t go to the game because I had a physical test at eight o’clock the next day. Wolfgang Mozart could compose elaborate symphonies and operas at the age of sixteen. You could ask the librarian to help you find the book. |
| may | present or future possibilities
ongoing possibilities | In summer, the tiger shark may follow warm water currents as far south as New Zealand. Diet sodas may actually be causing people to gain weight. |
| might | present or future possibilities
past possibilities
ongoing possibilities | A cougar might not eat for several days at a time. Some form of primitive life might once have developed on Mars. My brother might be living in Australia next year. |
| had better | current or future desirability | You’d better register early, before enrollment closes in the more popular classes. |
| need to | current or future desirability | I think you need to see your dentist before that tooth gets worse |
| ought to | current or future desirability | We’re lost. We ought to stop and ask someone for directions. |
| should | current or future desirability
past desirability
present or future desirability | Hikers should carry extra food and clothing when hiking in the mountains. They should have left the demonstration before the violence started. When the first frost occurs, we should see the beginning of the fall colors. |
| have/has to | current or future necessity | I have to talk to my professor about my research project. |
| had to | past necessity | Last semester I had to hire a tutor to help me with calculus. |
| have/has got to | current or future necessity | The government has got to develop a better plan for dealing with epidemics. |
| must | current or future necessity
possibility now
past possibility
ongoing possibilities | Students must pay all tuition and fees on time. The birds are singing, so it must be spring. Tony got an A in physics, so he must have worked hard. My roommate isn’t back yet. She must be having a good time at the beach. |
| would | past habit | In the early twentieth century, people would ride the trolley to work |
| used to | past habit | My mother used to take us to the library every Saturday. |
| would rather | preference | I‘d rather play tennis than go swimming. |
Causative verbs are verbs that cause an action. They can be used to express a request, an inducement, or to enable or allow someone to do something. Verb phrases with causative verbs are often followed by an indirect object.
Causative verb + indirect object + infinitive
| Causative | What it means | Examples |
| make | order, request | Our apartment manager makes everyone follow the rules. |
| have | request | Professor Jones always has us work with a partner in class. |
| get | persuade | My cat gets me to open doors for him all day long. |
| help | make capable | The new program helps children appreciate art. The new program helps children to appreciate art |
| let | allow | Some dog owners always let their dogs run loose. |
| His supervisor made him correct the errors in the monthly report Doctor Armstrong had her assistant prepare the handouts. We should have gotten someone to give us a ride home. |
Causative verbs can express the future tense.
| I hope my roommate will help me clean the apartment Next year the university will let students register for courses online. |
The voice of a sentence is divided into active voice and passive voice. Voice refers to the relationship between the subject and the predicate verb of a sentence.
In active voice sentences, the subject is the doer of the predicate action, emphasizing that someone or something has done a certain behavior or action.
| William Herschel discovered Uranus in 1781. S V O |
In a passive voice sentence, the subject is the recipient of the action of the predicate. emphasizing the recipient of the action rather than the doer. The doer of the action is placed after the verb or is omitted.
| Uranus was discovered by William Herschel in 1781. S V |
Sentences using the passive voice often appear in written English, especially in scientific and technical English, business English and government publications, to emphasize the action or the recipient of the action.
The passive voice of a verb is formed by auxiliary verb be plus the past participle of the verb. The passive voice is used in many tenses. The tense of the auxiliary verb be changes depending on the tense of the sentence.
| Tense | Examples |
| simple present tense | A language is considered “dead” when it is no longer used for oral communication. |
| present continuous tense | Algebra and physical science are now being taught in the eight grade. |
| present perfect tense | Cats have been kept as domestic animals ever since humans started harvesting grains. |
| simple past tense | The first thermometer was invested by the great Italian astronomer Galileo. |
| past continuous tense | Theories of logic and binary numbers were being developed by Gottfried Leibniz in the 1600s. |
| past perfect tense | By the seventeenth century, chemistry had been recognized as a science. |
| simple future tense | The course Human Development will be offered only during the fall term. |
| future perfect tense | When the average worker retires, he will have been promoted at least twice. |
| infinitive | An innovative group of painters working in New York came to be known as “abstract expressionists”. |
Note: Present Perfect Progressive, Past Perfect Progressive, Future Progressive and Future Perfect Progressive cannot be used in passive voice.
The passive voice of verbs can be used with modal verbs such as will, can, may, might, should and must.
present: modal + be + past participle
past: modal + have/has been + past participle
future: modal + be + past participle
| Generalizations are scientific statements that can be verified with data. Stonehenge must have been built to serve a scientific or religious purpose. Any changes to the problem will be announced before the first speaker begins. |
NOTE: Adverbs usually come after verbs and before other auxiliary verbs.
| Jupiter’s smaller satellites can not be seen without a telescope. Some medications must always be taken with food. |
TIPS: In many cases, sentences written in the active voice are more convincing.
| Passive voice | Active voice |
| Ocean tides are caused by the moon. | The moon causes ocean tides. |
| A constant body temperature can be maintained by some animals. | Some animals can maintain a constand body temperature. |
| Paper is made from wood pulp. | We make paper from wood pulp. |
| Radar maps of several planets have been produced. | Scientists have produced radar maps of several planets. |
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