linking verbs: be, appear, seem, become, get, etc..

In the following sentences we use an adjective or noun after a verb to describe the subject or say what or who the subject is:
• Ian is a doctor. • She seemed unable to concentrate.
• The house became Peter's in 1980.
The adjective or noun in sentences like this is called a complement; the verb is called a linking verb. The most common linking verb is be; others include become, come, grow, turn; keep, remain, stay; appear, look, seem, sound, appear, seem
After appear (= seems true) and seem we sometimes use to be before an adjective:
• He seems/appears (to be) very nervous.
We include to be before the adjectives alive, alone, asleep, and awake:
• I didn't go in because she appeared to be asleep, (not ...appeared asleep.)
Before a noun we include to be when the noun tells us who or what the subject is, but can often leave it out when we give our opinion of the person or thing in the subject. We leave out to be in more formal English. Compare:
• He went through what appeared to be a locked door, (not ...appeared a locked door.)
• She seems (to be) a very efficient salesperson.
Notice that we include to be before -ing forms (growing, moving, etc.):
• It seems to be growing rapidly.
become, come, get, go, grow, turn (into) We use the linking verb become to describe a process of change. A number of other linking verbs can be used instead of become, including come, get, go, grow, turn (into).
We use get rather than become in informal speech and writing, in imperatives, and in phrases such as get broken, get dressed, get killed, get lost, get married, get washed:
• Don't get upset about it!
• Where did you live before you got married}
We prefer become when we talk about a more abstract or technical process of change:
• He became recognised as the leading authority on the subject.
• Their bodies have become adapted to living at high altitudes.
We use become, not get, if there is a noun after the linking verb describing a change of job:
• Dr Smallman became an adviser to the US government.
We use go or turn, not get, when we talk about colours changing:
• The traffic lights turned/went green and I pulled away.
We often use go when we talk about changing to an undesirable state. For example, we use go, not turn or get, when we say that somebody becomes deaf, blind, bald, or starts to behave in a mad or excited way; and also in phrases such as go bad/off/mouldy (food), go dead (a telephone), go missing, and go wrong.
• The children went completely crazy at the party.
• My computer's gone wrong again.
We use turn to say that somebody reaches a particular age, and turn into when we say that one material or thing becomes another:
• He turned sixty last year.
• In my dream all the sheep turned into wolves.
After the verbs come, get, and grow we can use a to-infinitive. Come and grow are often used to talk about gradual change. We can't use a to-infinitive after become:
• I eventually came/grew to appreciate his work, (not ...became to appreciate...)
• I soon got to know their names, (not ...became to know...)