They then put the 100-mL beaker in the 250-mL beaker and heat over a burner until the water temperature reaches 50 degrees.
(They; put; the 100-mL beaker; in the 250-mL beaker and heat; T:until the water temperature reaches 50 degrees; T:then) (the water temperature; reaches; 50 degrees)
They the water temperature
put reaches
the 100-mL beaker in the 250-mL beaker and heat T:until the water temperature reaches 50 degrees T:then
50 degrees