by mixture
混ぜ合わせて
by monorail
モノレールで
by moonlight
月の明かりで
by mutual consent [agreement]
合意の上で
By my reckoning it's 20%.
ざっと２割だ
by natural consequences
自然の成り行きで
by no stretch [not by any stretch] of the imagination
いかに想像をたくましくしてみても…ではない
by occasion of illness
病気のために
by one's bootlaces
（敵に対し）１人で向かって
by [on] one's faith
誓って，確かに
