I don't think the experiment is ___ failure, because it has provided us with ___valuable experience for our future tests.
| A．不填; 不填 | B．不填; a | C．a; a | D．a; 不填 |
Word has come _____some American guests will come for a visit.
| A．what | B．whether | C．when | D．that |
Great changes_____ in the small city in the last 20 years.
| A．have taken place | B．took place | C．had taken place | D．are happening |
----Kate really upset Granny.
-----I’m sure she didn’t______.
| A．want so | B．mean to | C．have to | D．hope so |
----Why did you go back to the shop?
-----I left my friend _____there.
| A．waiting | B．to wait | C．wait | D．waits |
I advise you to give up smoking for it is _____to your health.
| A．harm | B．harmless | C．harmful | D．harmfully |