Correct Answer: B

Rationale: The correct answer is writing a postcard (Choice B). A postcard is a casual form of communication, typically sent to friends or family, making it a suitable context for informal language. Using informal language in a seminar (Choice A) would be inappropriate as it is a formal setting where professional language is expected. Talking to your boss (Choice C) and participating in a professional conference (Choice D) also require formal language to maintain professionalism and respect for the workplace environment.

Correct Answer: A

Rationale: The correct answer is 'A: Coordinate clause.' In the sentence 'I ate, and he drank,' 'I ate' and 'he drank' are coordinate clauses. They are both independent clauses that are joined by the coordinating conjunction 'and.' A coordinate clause is a type of independent clause that is equally important and balanced within a sentence. A dependent clause cannot stand alone as a complete sentence and relies on an independent clause. A subordinate clause is a type of dependent clause that functions within a sentence to provide additional information but does not express a complete thought. An independent clause, on the other hand, can stand alone as a complete sentence.

Correct Answer: B

Rationale: The correct answer is B, compound sentence. This sentence consists of two independent clauses ('The sky is blue' and 'the grass is green') that are joined by the coordinating conjunction 'and.' A simple sentence contains a single independent clause. In contrast, a complex sentence has one independent clause and at least one dependent clause. A compound-complex sentence consists of multiple independent clauses and at least one dependent clause, which are not present in the given sentence, making choices A, C, and D incorrect.

Correct Answer: D

Rationale: The correct answer is D (Henry) because the adjectives 'strong and healthy' describe 'Henry.' In this sentence, 'Henry' is the subject being described as strong and healthy, not 'weeks,' 'his,' or 'surgery.' While 'weeks' and 'surgery' are nouns mentioned in the sentence, they are not the nouns being described by the adjectives in question. 'His' is a possessive pronoun referring to Henry and does not match the criteria of being directly described by the adjectives 'strong and healthy.' Therefore, 'Henry' is the noun that the adjectives specifically describe in this context.

Correct Answer: C

Rationale: The correct verb to use in this sentence is 'are.' In English grammar, when the subject is plural like 'girls,' the correct form of the verb to use is 'are.' Choices A, B, and D are incorrect because 'is' is singular, 'am' is first-person singular, and 'ares' is not a valid verb form in English. Therefore, the correct answer is 'are' to match the plural subject 'girls.'