Possible Clues:

• Together
• All together
• All speaking or singing as one
• Altogether sounded like one popular, small place of learning for one of those in Trinity
• All together at the same pitch
• How Gregorian chants are sung
• All together with one sister and one relative
• One religious lady and one boy singing the same tune
• As one child under 11 hugs sister
• All at once, one transgression in a term of grammar coming up