_____ some mammals came to live in the sea is not known. [ ]A. WhichB. Si

题型：广东省月考题难度：来源：

_____ some mammals came to live in the sea is not known. [ ]
A. Which
B. Since
C. Although
D. How

答案

举一反三

If you often feel tired and can"t focus your attention, that is________you have to stop working too
hard and to have a rest.[      ]
A. why
B. whether
C. when
D. what

题型：陕西省同步题难度：| 查看答案

-I went to see my friends off at the airport.
-Is that________you were late for the important meeting.[     ]
A．because
B．why
C．how
D．reason

题型：同步题难度：| 查看答案

You are saying that everyone should be equal，and this is________I disagree.[     ]
A．why
B．where
C．what
D．how

题型：同步题难度：| 查看答案

He always thinks________he can do more for the people.[     ]
A．what
B．how
C．of how
D．of what

题型：同步题难度：| 查看答案

-You see, I"m poor in maths, you are not good at English, and…
-That"s ________we should help each other.[     ]
A．when
B．where
C．how
D．what

题型：同步题难度：| 查看答案