What is the past tense of the verb 'discover'?

Correct Answer: B

Rationale: The past tense of the verb 'discover' is 'discovered.' In this case, the scientist already found a new species of butterfly, indicating a past action. 'Discovered' is the correct past tense form of 'discover.' The other options do not represent the past tense form of the verb. 'Discovers' is present tense, 'discovering' is present participle, and 'discovery' is a noun, not a verb tense.

Correct Answer: B

Rationale: In the sentence, 'beautiful' is used as an adjective to describe the flowers. To transform the adjective 'beautiful' into an adverb, you add '-ly,' resulting in 'beautifully.' Adverbs modify verbs, adjectives, or other adverbs, offering more details on how an action is performed. Choice A ('beautiful') is the original adjective form and not the adverb form. Choice C ('beautification') is a noun, not an adverb. Choice D ('beautify') is a verb, not an adverb.

Correct Answer: C

Rationale: The past participle of a verb is used to form various tenses and passive voice constructions. In this case, 'explained' is the correct past participle form of the verb 'explain'. The sentence structure indicates a completed action in the past, which aligns with the use of the past participle. Choice A, 'explains,' is the present tense form of the verb, not the past participle. Choice B, 'explaining,' is the present participle form of the verb, not the past participle. Choice D, 'explanation,' is a noun derived from the verb 'explain,' not the past participle form of the verb itself.

Correct Answer: C

Rationale: In this sentence, 'important' is the positive form of the adjective. When comparing two things, the comparative form is used, which is 'more important' in this case. 'More important' indicates a higher degree of importance when comparing two things. Therefore, 'more important' is the correct comparative form of the adjective 'important' in this context. Choice A ('important') is the positive form, not the comparative form. Choice B ('importantly') is an adverb, not a comparative form of the adjective. Choice D ('most important') is the superlative form, used to show the highest degree of importance among three or more things, not for comparing two things.

Correct Answer: D

Rationale: A compound-complex sentence consists of at least two independent clauses and at least one dependent clause. In option D, 'He enjoyed reading the book' is an independent clause, while 'because it was suspenseful' is a dependent clause, making it a compound-complex sentence. Choices A, B, and C do not meet the criteria for a compound-complex sentence as they either lack the required combination of independent and dependent clauses or do not contain multiple independent clauses.