The Hebrew conjunction waw (And) is better translated as “But,” since it introduces a change from the situation of verse 2. When she could hide him no longer means that she was not able to keep it a secret that she was protecting her three-month old baby boy. The reason is not given, but perhaps the child’s behavior and crying was becoming louder.
She took for him a basket means only that the mother “got” a basket (New English Bible and others). It does not suggest that she was the one who made or wove the basket.
The basket made of bulrushes was woven from a plant called papyrus. It was one of several types of reeds or “tall grass” that grew in the shallow water along the brink or “edge” of the Nile River. In cultures where papyrus is unknown, translators may express reeds as “tall grass” (see Good News Translation). The shape and size of the basket are not indicated, but it was a kind that could be made to float in water. (The same Hebrew word is used in Gen 6.14 for Noah’s ark.) Verse 6 indicates that it had a cover and could be closed. Therefore it may have been a common household item used as a place for storing personal and family things, or even food or produce. Translators in many languages will have a variety of words for baskets according to the size and material used, and they should pick a term which describes a basket large enough to hold a baby.
The bitumen and pitch were two thick, sticky substances used for sealing cracks in vessels of wood and reed. The distinction between the two is not clear, but the bitumen was probably a mineral substance, like asphalt, and the pitch probably came from certain plants. If bitumen and pitch are unknown, they may be combined as “tar” (Good News Translation), since the scientific identification is not important here. Their purpose, of course, is important, so Good News Translation adds “to make it watertight.” If tar is unknown, a translator may say, for example “a sticky substance to keep it from sinking,” or even “fixed the basket so that it would not sink.”
The mother placed it among the reeds at the river’s brink. This suggests that the basket was actually floating in water, for the reeds grew in the shallow water “at the edge of the river.” The word for reeds is a general term that includes bulrushes. (See the comment above.)
Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .