Sub and verb agreement 1

1.Studying grammar ___(be) very important for us to improve our English skills.

• a. are

• b. is

2.  Here ___ (be) some students who failed their exam last term.

• a. is

• b. are

3. 3.In the moss ...(nest, nests) many birds.

• a. nest

• b. nests

4. (Does, Do) the absence of reptiles affect the ecosystem?

• a. Does

• b. Do

5.During the brief summers (grow, grows) a rare moss.

• a. grow

• b. grows