You will find that an unbranded T-shirt is easy to dress up with a blazer.
BAF Shirt Mens Large Green Short Sleeve Stretch Lightweight Crewneck Tee Casual
You will find that this green goes well with black or gray bottoms.
True Classic Polo Small (3 pack) Olive, Gray, Navy
The solid pattern means this shirt is a reliable choice for travel or work.
The Commons Shirt Mens Large Blue Long Sleeve Rib Knit Crewneck Stretch Tee
The blue here is a classic navy, reliable for daily use.
Mens Athletic T Shirt Lightweight Moisture-Wicking Soft Performance Tee Black XL
The solid look here is timeless, so you can wear it season after season.