Watch the Ionian online guitar lesson by Chris Buono from Modes That Matter
In the playing of the major scale it’s best to avoid resolving a melodic idea on the 4th degree as it’s widely agreed its an unwanted dissonance. Not to worry you still have six other notes that will sound great in almost any capacity. At the same time, if you can make it work, by all means: PLAY IT! A good approach is to use the 4th as a passing tone. When done correctly it contributes to some very catchy phrases. In the end, it’s all in how you play them.
Speaking of: phrasing is the all-encompassing term used to describe how you play a melodic figure or lick. It is phrasing that makes a mode come to life and be heard as a sound all its own and not just a scale starting on said degree of a parent scale. In fact, improvising is all about phrasing!!