Correct Answer: (C) couldn’t help laughing​

The idiom “couldn’t help” expresses inability to control an action, requiring a gerund (-ing form) after “help.” This fits the context of an uncontrollable reaction to a funny movie.​

Option Analysis

(A) could help laughing
This reverses the idiom’s meaning, implying the ability to stop laughing, which contradicts the funny movie context. “Could help” lacks idiomatic use and needs a gerund, but the logic fails.​

(B) couldn’t help laughed
Grammatically wrong: “couldn’t help” demands a gerund like “laughing,” not past tense “laughed.” This violates the fixed structure of the expression.​

(C) couldn’t help laughing
Correct: Follows the rule where “can’t/couldn’t help” + gerund indicates involuntariness, as in Cambridge Dictionary examples like “I couldn’t help laughing.” Matches past tense and meaning perfectly.​

(D) could helped laughed
Incorrect on multiple levels: “Could” takes base “help,” not “helped” (past participle); lacks gerund after “help”; “laughed” is wrong form.​

The couldn’t help laughing grammar rule is essential for English learners and competitive exams, where idioms like couldn’t help laughing test verb patterns. This phrase means being unable to stop an action due to strong impulse, always followed by a gerund.​

Why Gerund After “Help”?

“Can’t/couldn’t help” acts as a fixed expression requiring V-ing, similar to “can’t stand” or “it’s no use.” Examples:​

• “The joke was hilarious; I couldn’t help laughing.”​

• “She couldn’t help crying at the sad ending.”​
  Avoid errors like infinitives or past tense, common in sentences like “The movie was funny and I _________.”​

Common Mistakes to Avoid

• Could help laughing: Wrong meaning (able to stop).​

• Couldn’t help laughed: No gerund.​

• Couldn’t help but laugh: Acceptable variant, but gerund form is standard without “but.”​
  Use for exams: Practice with MCQs on couldn’t help laughing idiom.​

Exam Tips

Focus on context—funny scenarios demand negative “couldn’t.” Related: “Can’t help doing” for present. Master this for CSIR NET English or grammar tests.​