A major seventh suspended fourth chord is composed using a root/1st, perfect 4th, perfect 5th and a major 7th (or R/1-4-5-7) intervals played simultaneously. Generally written as CMA7sus4 or CMA7sus, it is good practice to simply use an uppercase C with the uppercase letters MA followed by a super scripted 7sus4 to represent it in writing (ie: CMA7sus4).
The major seventh suspended fourth chord has a major tonality even though it lacks a 3rd degree, it's the major seventh interval that gives it this quality. If the perfect 4th (suspended 4th) is resolved to the major 3rd the major quality becomes even clearer.
It is not necessary to resolve the major seventh suspended fourth chord, it is merely a tonal tool we can use if required.
Major seventh suspended fourth chord profile
|Intervals||root/1st, perfect 4th, perfect 5th, major 7th or R/1-4-5-7|
|Stability||Somewhat dissonant, unresolved|
|Common names (examples in C)||CMA7sus4, CMAsus|
|C Major seventh suspended fourth chord voicing #2|