I need someone else to tell you "why" for your first question.a few questions about definite article "the"
1. "Swimming is second in importance only to track and field events."
Why don't we add "the" in front of "second"? as follows,
"Swimming is the second in importance only to track and field events."
2. "My neighbor asked me to go for a walk, but I dont think I've got the energy." In this sentence , can we omitted "the"?
No, it's the specific enery needed to go on the walk. I don't have much energy is a general statement. I don't have the energy (to go for a walk) is a specific statement.
3."Do you know the English for "搭“？ I'm afraid I don't. I'm not interested in the English." Can "the" be omitted?
Not only can it be omitted, it needs to be omitted. It's wrong.
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