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When I was a little child, I fell in love with playing basketball. When I had some leisure time, I would find a court to play. I ____ been doing this all along. Finally I became a professor. My students often kindly invite me to play basketball with them. Regretfully, I found out that I am too old to be involved in this kind of sports. Twice, I almost got hurt. The students were embarrassed. I switched to tennis playing after I became forty years old and have been doing so ever since. I have never been hurt by playing tennis.

Which word should I use to fill in the blank, have or had?
Comments  
I'd use had.
"Had", without hesitation, according to the context.
Students: We have free audio pronunciation exercises.
Everything in the context is written in the past point of view. There is nothing to suggest that the author is still playing basketball in present time. In fact, as the story progresses, we see that it is quite certain that the author no longer plays basketball in present time.

The choice has to be had.

CJ
CalifJimEverything in the context is written in the past point of view. There is nothing to suggest that the author is still playing basketball in present time. In fact, as the story progresses, we see that it is quite certain that the author no longer plays basketball in present time.
There's this sentence which messes up the tenses:

My students often kindly invite me to play basketball with them.
Yes, indeed. Surprisingly, the sudden shift of point of view is not too shocking in this example! I've seen cases that were much more nerve-jangling than this one! Emotion: smile

CJ
Students: Are you brave enough to let our tutors analyse your pronunciation?
CalifJimYes, indeed. Surprisingly, the sudden shift of point of view is not too shocking in this example! I've seen cases that were much more nerve-jangling than this one! Emotion: smile
Are shocking and nerve-janglingparallels and synonyms here?Emotion: rolleyes
shocking, jarring, unnerving, disturbing
They all have similar meanings, yes.
nerve-jangling
also has a similar meaning, but I doubt you will find it in a dictionary. It is an adjective I formed from to jangle one's nerves.

CJ
Thank you againEmotion: smile
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