（1）主语从句 （2）宾语从句 （3）表语从句
例：Whether the Government should increase the financing of pure science at the expense of technology or vice versa（反之）often depends on the issue of which is seen as the driving force.
例：They are the possessions of the autonomous（self-governing）man of traditional theory， and they are essential to practices in which a person is held responsible for his conduct and given credit for his achievements.
例：While there are almost as many definitions of history as there are historians， modern practice most closely conforms to one that sees history as the attempt to recreate and explain the significant events of the past.
例：This trend began during the Second World War， when several governments came to the conclusion that the specific demands that a government wants to make of its scientific establishment cannot generally be foreseen in detail.