The students, as well as the teacher, are nervous about the test.

Question:

The students, as well as the teacher, (is, are) nervous about the test.

The students, as well as the teacher, are nervous about the test.

Explanation:

Is and are are both present tense conjugations of the verb ‘to be’. Is is the singular form of be whereas are is the plural form of be. Therefore, the main difference between is and are is that is is singular whereas are is plural.

Singular- (of a word or form) denoting or referring to just one person or thing.

Plural- (of a word or form) denoting more than one, or (in languages with dual number) more than two.

glamis thou art, and cawdor; and shalt be what thou art promis'd; yet do i fear thy nature; it is too full o' the milk of human kindness to catch the nearest way: thou wouldst be great; art not without ambition; but without the illness should attend it. what thou wouldst highly, that wouldst thou holily; wouldst not play false, and yet wouldst wrongly win: thou'dst have, great glamis, that which cries, "thus thou must do, if thou have it: and that which rather thou dost fear to do than wishest should be undone." hie thee hither, that i may pour my spirits in thine ear; and chastise with the valor of my tongue all that impedes thee from the golden round, which fate and metaphysical aid doth seem to have thee crown'd withal.  

he lacks ambition.  

he is hesitant.  

he lacks courage.  

he has moral scruples.