You haven’t been to the West Lake, have you—_____. But I will go there with my parents this summer vacation.

One should take ______ of his strengths to make up for his weaknesses.

I used to online a lot, but now I am used to with my friends.

Exploring ________ space is exciting, yet dangerous.There is _______need for both robots and humans for space exploration.

Here _____ This is our classroom