下图为“我国华北地区1954~2002年降水量变化示意图”,读图完成下列问题。华北地区降水量年际变化的最大值约为( )
1964年华北地区的年降水量高达650mm,原因可能是( )
____the sketch of Xiao Shenyang made a _____has been known to us all.
That Xiao Shenyang was elected_____model worker of May Day caused ____enthusiastic discussion in China.
----What do you know the _____ of are the pig influenza in humans? ---- usually similar to regular human seasonal influenza .
People go out with masks,________.
The dead rate is _____ pigs and recovery usually ______ within 7-10 days. A low in; occurs B.rich in;happens C.high in; came about D.poor in;took place