Looking on the internet deeply has found these results:

I had to study english is the most popular phrase on the web.

english had to have been studied 10 results on the web	I had to study english 1286 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	Oct 13, 2013 ... I had to study English. I needed to study English. I tried to study English. I traveled to study English. But, for some verbs, it's incorrect: I ended up�... May 15, 2013 ... ... is impossible because all lessons in college is by english and also all exams too so i felt that i had to study english if i want to succes in future�... For me it was all right to speak only Portuguese. But of course I didn't have much choice, so I had to study English like everybody else. What is this? This is a dog�... I had to study English literature instead, to be a teacher, and I had to commute one hour and half each day to the university. While I was at the university, I started�...

english had to have been studied

10 results on the web

I had to study english

1286 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

Oct 13, 2013 ... I had to study English. I needed to study English. I tried to study English. I traveled to study English. But, for some verbs, it's incorrect: I ended up�...
May 15, 2013 ... ... is impossible because all lessons in college is by english and also all exams too so i felt that i had to study english if i want to succes in future�...
For me it was all right to speak only Portuguese. But of course I didn't have much choice, so I had to study English like everybody else. What is this? This is a dog�...
I had to study English literature instead, to be a teacher, and I had to commute one hour and half each day to the university. While I was at the university, I started�...