多 た環 かん芳香 ほうこう族 ぞく炭化 たんか水素 すいそ

takan hōkōzokutankasuiso

1. Not polycyclic aromatic hydrocarbons.

1. Was a polycyclic aromatic hydrocarbon.

1. Polycyclic aromatic hydrocarbons

1. Polycyclic aromatic hydrocarbon; PAH

1. It is not a polycyclic aromatic hydrocarbon.

1. It's not polycyclic aromatic hydrocarbon.

1. Was a polycyclic aromatic hydrocarbon.

1. Polycyclic aromatic hydrocarbon; PAH

1. Is not a polycyclic aromatic hydrocarbon.; It is not a PAH.

1. Wasn't polycyclic aromatic hydrocarbon.

1. Probably polycyclic aromatic hydrocarbon.

1. Was not a polycyclic aromatic hydrocarbon.

1. Wasn't polycyclic aromatic hydrocarbon.

1. Probably polycyclic aromatic hydrocarbons.

1. Was not a polycyclic aromatic hydrocarbon.

1. If it were polycyclic aromatic hydrocarbons; Were it polycyclic aromatic hydrocarbons

1. if it is a polycyclic aromatic hydrocarbon; if it’s a PAH

1. If/when polycyclic aromatic hydrocarbons