Wateriscomposed_______hydrogenandoxygen.
A
be composed of：由 …組成。句意：水是由氫與氧化合而成的。
Itrainedhardyesterday,______preventedmefromgoingtothepark.
Hewouldhavegivenyoumorehelp,ifhe________sobusy.
Theyareeager_______abroad.
CharlesSmith,______wasmyformerteacher,retiredlastyear.
Whenyou're_____acrisis,itoftenhelpstotalktosomeone.
