First Image - Lobelia angulata, Second Image - no idea could be a Juncus, Triglochin or Isolepis - need an image of whole plant. Third image - Isolepis, Fourth Image - Juncus - most probably J. planifolius but could be J. caespiticus - need to see inflorescences. Last Image Juncus (probably) or Isolepis.
For all of these 'monocots' you need to post up clear images of fertile material