assert 肯定的说，断言;维护，坚持 2次

We shall probably never be able to ______ the exact nature of these sub-atomic particles.(02.6—46)

A) assert B) impart C) ascertain D) notify

The police are trying to_ what really happened.(04.6—53)

A) ascertain B) assert C)avert D)ascribe

authorize 授权，批准 3次

Some American colleges are state-supported, others are privately ________, and still others are supported by religious organizations.(02.1—68)

A) ensured B) attributed C) authorized D) endowed

1　told　him　that　I　would　_____________　him　to　act　for　me　while　I　was　away　from　office.　(03.6—69)

A)　authorize　B)　justify　C)　rationalize　D)　identify

A membership card ________the holder to use the club’s facilities for a period of twelve months.(03.9—56)

A) approves B) authorizes C) rectifies D) endows