Looking on the internet deeply has found these results:

four-year study is the most popular phrase on the web.

four years study 1118,000 results on the web	four-year study 1411,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
year study on children aged 6 to 10 who showed signs of baldness. year study found that a 10 year study on children aged 6 to 10 who showed signs of baldness. The Dermatology Faculty of Bologna University carried out a four The four In a four year study, 1,000 people were made to exercise four hours a week for 20 weeks. The Dermatology Faculty of Bologna University carried out a four	The Dermatology Faculty of Bologna University carried out a four The Dermatology Faculty of Bologna University carried out a four At the end of the four year study, 1,000 people were made to exercise four hours a week for 20 weeks. year study, 21% of the patients treated with Xenical had lost more than 10% of their body weight, compared with 10% of the patients who received placebo. year study on children aged 6 to 10 who showed signs of baldness. In a four year study on children aged 6 to 10 who showed signs of baldness.

four years study

1118,000 results on the web

four-year study

1411,000 results on the web

More popular!

year study on children aged 6 to 10 who showed signs of baldness.
year study found that a 10
year study on children aged 6 to 10 who showed signs of baldness.
The Dermatology Faculty of Bologna University carried out a four
The four
In a four
year study, 1,000 people were made to exercise four hours a week for 20 weeks.
The Dermatology Faculty of Bologna University carried out a four

The Dermatology Faculty of Bologna University carried out a four
The Dermatology Faculty of Bologna University carried out a four
At the end of the four
year study, 1,000 people were made to exercise four hours a week for 20 weeks.
year study, 21% of the patients treated with Xenical had lost more than 10% of their body weight, compared with 10% of the patients who received placebo.
year study on children aged 6 to 10 who showed signs of baldness.
In a four
year study on children aged 6 to 10 who showed signs of baldness.