A．When we are tired.
B．When we cannot look at flowers.
C．When we cannot change our lives.
D．When we are doing exercises.
参考答案A
解析:A
你可能喜欢
A．Going to bed earlier.
B．Working even harder.
C．Reading more books.
D．Finding its cause.
A．Hit the Control key and hold down the Space key.
B．Hit the Shift key and hold down the Delete key.
C．Hit the Space key and hold down Shift key.
D．Hit the Delete key and hold down the Space key.