The phrase "differentiate clearly" is correct and can be used in written English.
This phrase is typically used when one wants to make a clear distinction between two or more things. For example, "We need to differentiate clearly between our core values and our priorities for this project."
Proposals should differentiate clearly between the seed grant project and the larger research program.
When will we differentiate clearly between sick and bad, between ill and evil?
At the present time, O Lord... you differentiate clearly between us and the Jews or pagans; thus do you spurn their vows, their prayers, and their offerings; thus do you show that these are repugnant to you...
Israelis differentiate clearly between various levels on a continuum of military action.
Two studies did not differentiate clearly between organisms.
BUs and AT demonstrated particularly poor ability for EPA plus DHA (or EPA or DHA alone; data not shown) to differentiate clearly between groups.
Nevertheless the South Korean breakthrough makes it more urgent than ever that legislation is passed differentiating clearly between therapeutic and reproductive cloning permitting the former and prohibiting the latter.
We also used a drug treatment regimen that differentiates clearly between initial and long-lasting differences in drug responsiveness.
Differentiating clearly between content-based and writing-based criteria may help reviewers focus on the parts of manuscripts they are most competent to judge.
We examined acute and sensitized locomotor effects of methylphenidate in adolescent and early adult male Sprague Dawley (SD), spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats using a drug regimen that differentiates clearly between initial and enduring differences in drug responsiveness.
But perhaps one day we'll be confident enough with difference to differentiate more clearly between good faith cock-ups, halfwittedness, generational backwardness and deliberate discrimination.
