In the past few years，many schools__the ways of doing morning exercises．（ ）
| A． |
change |
B． |
changes |
| C． |
will change |
D． |
have changed |
You looked unhappy just now．_____？
I missed the school bus and arrived late for class．（ ）
| A． |
What did you eat for lunch |
| B． |
How was your picnic |
| C． |
What happened to you |
| D． |
How did you go there |
The PLA Navy（中国人民解放军海军） has been greatly helping keep world peace．As a Chinese， I am_____ it．（ ）
| A． |
responsible for |
B． |
proud of |
| C． |
full of |
D． |
known for |
With the rapid progress in high technology， 5G_____ around most parts of China in the near future．（ ）
| A． |
is used |
B． |
is using |
| C． |
will use |
D． |
will be used |
_____ we continue to kill elephants for their ivory，we humans will lose them in the end．（ ）
| A． |
If |
B． |
Before |
C． |
Until |
D． |
Although |
The program， Everlasting Classics， encourages _____ to read more classics．（ ）
| A． |
we |
B． |
us |
C． |
our |
D． |
ours |