One instrument is the kazoo.
Those letters spell isthmus.
Human
String instrument four letters
barometer
The Alamo is a landmark that has five letters.
accordion
The CORNet.
· Dulcimer
The organ is a musical instrument.
The homophone of sees that is five letters is "seas."
The think system is if you think about the melody and you hum the melody, when you are presented with an instrument, you will be able to play the melody.
Flute.