ctile -ctil- gismu

x1 is a quantity of petroleum/oil from source x2.

See also grasu.

In notes:

ctilytergu'i
x1 is an oil lamp using petroleum-based products, illuminating x2 with light x1.
gaznatu
x1 is a quantity of natural gas, a mixture of methane with smaller amounts of ethane, propane, butane, other gaseous hydrocarbons and petroleum deposits
grasu
x1 is a quantity of/is made of/contains grease/fat/oil from source x2.
ligygrasu
x1 is solid [saturated] fat from source x2
likygrasu
x1 is liquid [unsaturated] fat (oil) from source x2.