—What does PM2.5 mean?—It's a professional ________ indicating the condition of air pollution.
His strong love for his country is _______ in his recently published poems.
He ______ busy yesterday, or he ______ you with your experiment.
—Can you come to attend our party tonight? -- Sorry, but I do wish I _________.
The newly-published book is written _________ for children, which is also popular with most parents.
_______ from the top of the towel, I find the city beautiful.