Explanation: The sentence suggests that Clara is serious about getting into shape for swimming. The word "vigorously" means with great energy and enthusiasm, which fits best in this context. The other options do not fit: Clumsily – Means lacking coordination, which is not relevant. Mournfully – Means sadly, which does not match the positive determination. Reluctantly – Means unwillingly, which contradicts the idea of being "determined."

Explanation: The sentence suggests that measles is not only a children's disease but can also affect others. The word "exclusively" means only or solely, which fits best. The other options do not fit: Seriously – Does not make sense in this context. Occasionally – Means "sometimes," which does not convey the intended meaning. Nearly – Means "almost," which does not fit logically in the sentence.

Explanation: The sentence suggests that prices are continuously increasing, making it hard to plan a budget. The verb "rising" (which means going up or increasing) fits best. The other options do not fit: Reckoning – Means calculating or estimating, which is unrelated. Exceeding – Means going beyond a limit, but does not fit with "prices keep on." Raising – Incorrect verb form; "raising" requires an object (e.g., "raising prices").

Explanation: The sentence suggests that the new cashier demonstrated or showed that he is efficient and trustworthy. The verb "proved" fits best because it means to show something to be true through actions or evidence. The other options do not fit: Spoiled – Means to ruin or damage, which is incorrect here. Exaggerated – Means to overstate or magnify something, which does not fit. Upheld – Means to support or maintain, which is not the correct usage in this context.

Explanation: The sentence suggests that there is too much work to complete in one day, making any attempt to finish it pointless or ineffective. The word "useless" fits best because it means not helpful or effective. The other options do not fit: Sensitive – Means easily affected or emotional, which does not make sense here. Eager – Means enthusiastic, which contradicts the meaning of the sentence. Exaggerated – Means overstated, which is not the correct fit.

Explanation: The sentence suggests that the speaker did not anticipate or foresee leaving early. The verb "expect" means to think that something will happen, making it the best choice. The other options do not fit: Consult – Means to seek advice or information, which is unrelated. Wait – Does not fit grammatically in this context. Ask – Means to inquire or request, which does not convey the intended meaning.