Verb Complementation Patterns in Technical English

"Suggested refactoring" is correct: "suggest" takes a gerund (-ing form) as its complement, never a bare infinitive or a to-infinitive. This is a fixed pattern that must be memorized rather than derived from meaning — compare with "recommend", which behaves the same way ("recommended refactoring", not "recommended to refactor"). Option A incorrectly uses the to-infinitive, a very common error since many other verbs of advice (like "want" or "decide") do take to-infinitives, creating false pattern-matching. Option C uses the bare form with no complementizer, which is ungrammatical. Option D reorders the sentence into an unnatural and ungrammatical structure.

"Allows developers to query" is correct: "allow" follows the object + to-infinitive pattern (verb + object + to + base verb), a structure shared with verbs like "enable", "permit", and "expect". Option B incorrectly substitutes a gerund for the required to-infinitive after the object. Option C incorrectly tries to use a that-clause, which "allow" does not take in this construction. Option D omits the required "to" before the base verb, producing a bare infinitive after the object, which is ungrammatical with "allow" (though it would be correct with causative verbs like "make", e.g., "makes developers query" — the pattern depends entirely on the specific verb).

"Requires the service to handle" is the most natural and common complementation pattern for "require" in technical specifications: object + to-infinitive. Option B ("requires that the service handles") is grammatically acceptable in formal register using a that-clause, but note it uses the indicative "handles" rather than the subjunctive base form — mixing this with the subjunctive pattern ("requires that the service handle", without "s") is a separate, distinct construction and inconsistent verb forms across a document should be avoided; as a standalone pattern choice here, the to-infinitive form is cleaner and more standard in specs. Option A incorrectly uses a gerund ("handling") after the object, which "require" does not take in this pattern. Option D drops the required "to", producing a bare infinitive that is only correct in the separate subjunctive-that-clause pattern, not after a direct object without "that".

"Avoid hardcoding" is correct: "avoid" is one of a fixed group of verbs (along with "suggest", "consider", "recommend", "risk", "involve") that take only a gerund complement, never a to-infinitive. Option A incorrectly uses the to-infinitive pattern, a common overgeneralization from verbs like "want" or "need". Option C incorrectly introduces an unnecessary that-clause; "avoid" does not take this pattern. Option D uses the bare infinitive form with no complementizer at all, which is ungrammatical directly after "avoid".

"Remember configuring" (gerund) vs. "Remember to configure" (to-infinitive) is the correct pairing: "remember + gerund" refers to recalling a past action that already happened ("I remember configuring it" = I have a memory of doing it), while "remember + to-infinitive" refers to not forgetting a future obligation ("remember to configure it" = don't forget to do it). This is one of a small set of verbs (also "forget", "stop", "try", "regret") whose meaning changes depending on which complement form is used. Options B, C, and D all mix up which form pairs with which meaning, or combine "to" with an -ing form ("to configuring"), which is never grammatical in standard English.