Use the correct form of the verb "to register".
1.Every year staff members ... for language classes.
a) register. b) registers. c) will registered. d) have registered.
2.1000 staff members ... for classes since the programme started.
a) registered. b) were registered. c) are registered. d) have registered.
3.Mr. Brown ... for the first time two years ago.
a) registers. b) has registered. c) registered. d) would register.
4.Many people phoned for information while Mr. Brown ... .
a) register. b) registered. c) registers. d) was registering.
5.If Mr. Brown had known how difficult the classes would be he ... .
a) wouldn't register. b) didn't register. c) didn't registered. d) registered.
6.So last year he ... .
a) registering. b) didn't register. c) didn't registered. d) was register.
7.But now he realises that he ... .
a) had to register. b) has registered. c) should have registered. d) need register.
8.Moreover his boss insists that he ... .
a) register. b) registered. c) to register. d) registering.
9.His colleages also ask Mr. Brown why he has avoided ... for classes.
a) register. b) to register. c) registering. d) registered.
10.Now Mr. Brown wishes he ... for classes at the beginning of the year.
a) registers. b) has registered. c) registered. d) had registered.

в 8ом "B) registered" же

В 7- should have registered!!!!!

Про 7 согласна. Про 8 - нет!

8 мне кажется has registered, или просто register

Там сослагательное наклонение. Инфинитив без to.

1.register2. have registered3. registered4. was registering5.  wouldn't register6. didn't register7. should have registered8. register9. registering10. had registered