1. According to• Incorrect: According to me, she should have resigned earlier.• Correct: In my opinion, she should have resigned earlier.We do not give our own opinions with according to.2. Across and throughThe difference between across and through is similar to the difference betweenon and in. We use through to talk about movement in three dimensional spaceswith things on all sides.• We walked across the field. (= We were on the field.)• We walked through the wood. (= We were in the wood.)3. Adjectives ending in ly• Incorrect: She smiled friendly.• Correct: She smiled in a friendly way.• Incorrect: He laughed silly.• Correct: He gave a silly laughHere the error lies in using an adjective instead of an adverb. We use adverbs tomodify verbs. Most adverbs end in –ly; there are also a few adjectives that end in –ly. Examples are: costly, friendly, lively, likely, lonely, lovely, silly and ugly. Thereare no adverbs costlycostlily or friendlyfriendlily.4. Ago and before• Incorrect: His father died three years before.• Correct: His father died three years ago.