问题

People who can see with their eyes can’t understand _____ practical use Braille can be of for the blind.

A:how;
B:what
C:that;
D:whether;

正确答案是：

同类题型

Betty is often seen ____ the old man with his housework.

From time to time a crocodile has snatchedsomeone _______ he or she is even aware that the crocodile is there.

－Why do you look so excited， Timmy－I’ve just got a good________.

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The ___________ boy is very lovely .