Fortuitous formerly denoted "happening by chance" and later took on the meaning "fortunate". Such change of word-meaning is caused by ______。

Illustrate the differences between synonyms by analyzing the following groups of synonyms.

(a) understand and comprehend

(b) answer and respond

(e) allow and let

Explain the difference between full conversion and partial conversion by taking "valuables”and “the young" as examples.

Explain how context clues are used in the sentence “In spite of the fact that the fishermen were wearing sou’westers, the storm was so heavy that they were wet through."

Tell the difference between superordiates and subordinates, with the example words flower, lion, hammer, tool, animal and rose.

Turn the phrasal verbs below into noun compounds:

1) fall down

2) sit in

3) cry out

4) hang over

5) bring up .

Through which three channels does modem English vocabulary develop?

true idioms

elevation

conceptual meaning

morpheme