下列方程的变形是否正确？为什么？（1）由3+x=5，得x=5+3．（2）由7x=

– How did you know each other?

– Well, 2 years ago when I went on ______ trip to Yangshuo, we took ______    shelter from rain in the same cafe.

A．/; the

B．a; a

C．a; /

D．the; /

I was really busy these days, otherwise I _______ to your birthday party last night.

A．came

B．did come

C．should have come

D．would have come

PhotoShop中，按住【Ctrl】和回车键打开当前工具的选项面板。（）

单分型面注射模，主流道设在（），分流道设在（）。

自救器的主要用途是在井下发生（）事故时供井下人员佩戴脱险，免于中毒或窒息死亡。

A.瓦斯爆炸

B.煤尘爆炸

C.火灾