What is the test for using "in relation to" language in jury instructions in a sexual assault case?

Gallegos-Corrales relies on our recent decision in United States v. Mendoza, 11 F.3d 126 (9th Cir.1993). In Mendoza, we held a jury instruction similar to the one at issue in this case violated the defendant's due process rights because it omitted the "in relation to" language from its recital of the essential elements of the offense. Id. at 128. Moreover, we held that the error was not rendered harmless by other jury instructions which did use the "in relation to" language. Id. at 129.