Grammar and Vocabulary Completion: Form Follows the Slot
The two halves
This part asks you to fill blanks either with a grammatical form (verb tense, non-finite verb, article, preposition, conjunction) or with a derived word (noun from verb, adjective from noun, adverb from adjective). In both halves the same discipline applies: identify the slot, then choose the form it demands.
Grammar concepts to master
- Tense and aspect: time adverbials (since 2010, by the time, next Friday) determine tense; since/by the time often trigger perfect forms.
- Voice: decide whether the subject performs or receives the action before choosing active or passive.
- Agreement: find the true head noun, ignoring long prepositional phrases.
- Non-finite verbs: after prepositions use -ing; purpose uses to do; result or accompanying action uses doing/done.
- Articles and prepositions: countability, first vs second mention, and fixed phrases (in charge of, on behalf of, at risk).
Word-formation concepts
- Decide the part of speech from the slot: after an article or possessive you need a noun; before a noun you need an adjective; modifying a verb or adjective you need an adverb.
- Know common prefixes and suffixes, and negative prefixes (un-, in-, im-, dis-, mis-).
- Watch spelling: consonant doubling, dropped e, y to i.
Traps
- Filling a verb slot with the right tense but the wrong voice.
- Deriving a correct-looking word of the wrong class ("succeed" where "success" is required).
- Supplying two words when the instruction allows one.
- Ignoring irregular past forms and past participles.
Worked example
"Her ____ (explain) was so clear that even beginners understood." The slot follows a possessive and is the subject: a noun is needed → explanation, not explain or explaining.
Rule of thumb
Cover the blank, name the part of speech the sentence needs, and only then look at the prompt word.