He is one of the world's (1) ______experts on artificial intelligence (A.I.).

Choose the word whose underlined word is pronounced differently from the others.

Choose the word whose underlined word is pronounced differently from the others.

Choose the word whose stress pattern is different from that of the others.

Choose the word whose stress pattern is different from that of the others.

Choose the best option A, B, C or D to complete the sentence.

Our national heritage of biological___________ is an invaluable and irreplaceable resource.

Choose the best option A, B, C or D to complete the sentence.

We need to work harder to remain competitive __________other companies.

Choose the best option A, B, C or D to complete the sentence.

After three years’ hard work, he was___________.