But at other moments you will find him gentle and weak, ________ he cries about the lost lives of people drowned in ships that have sunk．

A．as with

B．as for

C．as to

D．as when

They form a polar molecule, ________ is, ________ with a slightly positive end and a slightly negative end．

A．which; that

B．it; one

C．that; one

D．one; that

They find themselves surrounded by colorful rocks, fishes, seashells and plants, all ________ slowly in the blue water．

A．waving and moving

B．waved and moved

C．waved and moving

D．waving and moved

Even though the pure water is ________ gives sea water its main properties, the salinity of sea water affects both its weight and freezing point．

A．the one

B．which

C．what

D．that

Mike is Mrs．'pet student, ________ all her students no one else is as nice as he．

A．because

B．because of

C．with

D．as

He came running along and climbed ________ the train just as it was about to leave．

A．aboard

B．board

C．abroad

D．on abroad

Just as one of the parents ________ it, students today are under far greater stress than ever．

A．says

B．speaks

C．puts

D．gets

All the classmates are trying to make the party ________．

A．success

B．a success

C．succeeded

D．successfully

Mum had to cook different courses for Mike, for his tastes are ________．

A．various

B．variety

C．vary

D．varied

________, his discovery has created a stir in scientific circles．

A．As is believed

B．It is believed

C．He is believed that

D．Who believed that