1.was
2. with – an expression “with the help of”.
3. for – a word used in English to show who is intended to have or use something or where something is intended to be put. In this sentence “…words for dictionary.”
4. but – in this sentence “but” is used to introduce a phrase that contrasts with what was said before “hard words but also many ordinary ones”.
5. a – an indefinite article “a” must be used before a noun in singular.
6. more – is used for saying that a particular quality/thing/topic is stronger than it was before, or stronger than you expected or hoped. In this text dictionaries are being compared, and this one mentioned in this sentence is much better than the previous one.
7. as – The sentence “... as many different meanings of the word as he could” indicates that the expression “as many... as” must be used. And “as...as” structure is often used with quantity expressions such as “much” or “many”.
8. themselves – Reflexive pronouns are not used on their own as the subject of a clause, but they can be used with a noun to emphasis the subject: “… words themselves,…”.
9. were – a negative form in past simple. If the sentence starts in past simple, then it must be continued in the same tense.
a) большой улов
2) a brainwave
b) полет мысли
3) a blind alley
c)тупик
4) a bright spark
c) идея