单选题 The road ______ last year.
builds
built
was built
is built
单选题 —Have you heard about that ear accident near the school? —Yes, luckily no one ______.
hurt
was hurt
has hurt
were hurt
单选题 —Does she like singing English songs? —Yes. She ______ to sing English songs in her room.
often does
is often heard
often hears
often is heard
单选题 同温同压下,等物质的量的氢气和氦气具有相同的( ).
原子数
体积
中子数
质量
单选题 当溶液中含有大量H+时,也能同时大量存在的离子是( ).
S2-
SO32-
SO42-
CO32-
单选题 在△ABC中,如果a:b:c=2:3:4,那么( ).